Multiple Shadow Clone Jutsu.
The reason it's classified as a forbidden technique by the Second Hokage is simple.
The amount of chakra this technique requires is excessively vast, far beyond what an ordinary ninja can endure. Moreover, at the moment the technique ends, various negative effects on the user's mental state are directly reflected. Those lacking resilience or with weak mental fortitude can instantly be overwhelmed or even driven insane. Generally speaking, only a few elite jonin, who have experienced numerous life-and-death trials and are at the top of their game, can use this jutsu.
However, Naruto is different.
Even as a newly-minted Genin, not relying on the Nine-Tails, he already possesses more than twice the chakra of Kakashi.
(In the original story by the time of Shippuden, it's estimated to be over four times Kakashi's chakra, conservatively speaking.)
Still, considering the mental stress.
Naruto intentionally limits the number of clones.
Even so, the hundreds of clones he created this time shocked Sasuke, who was standing nearby. At that moment, Sasuke truly realized the extent of this classmate's strength. Leaving aside everything else, just the close-quarters combat with Kakashi at the beginning, and the number of clones he has summoned, even Sasuke must admit that he has little chance of winning.
This further stimulated Sasuke's proud but currently fragile heart.
"A tactic of overwhelming numbers? Heh, Naruto, do you think this will work on me?"
Even though Naruto created hundreds of clones at once, Kakashi, not far away, was only surprised by Naruto's chakra levels.
Ultimately, the gap in strength is clear.
Kakashi still maintains a calm demeanor.
"Whether it works or not, we'll find out soon, Kakashi-sensei!"
Simultaneously, a thunderous voice.
"Alright, let's go!"
Words spoken as they descended.
Explosive figures.
"Boom!"
Confronting the exploding shockwave.
From all directions, the Naruto clones that were converging on them drew shurikens and kunai from their pouches, appearing in their palms as they closed in.
Directly showing their explosive power.
At the same time, as Naruto initiated the attack, Sasuke, standing aside, immediately moved to a safer position, circling around to find an opportunity to snatch the bell.
This time.
Naruto showed no restraint.
Their agile forms.
Closing in on their target.
With a swing of their arms.
From various angles, they attacked.
"Heh heh!"
Accompanied by the ominous killing intent.
Kakashi, standing in the center, remained calm and moved forward instead of retreating.
"Clang!"
First, he blocked the frontal assault.
Then, in a swift motion, he swept his right leg.
With ultimate force.
"Peng peng peng!"
The clashes between the figures.
The unstoppable force.
"Whoosh."
One after another, the clones were sent flying.
Directly suffering severe damage.
"Pu pu pu pu."
In mid-air, these clones turned into white mist and quickly dissipated.
"Whoosh whoosh whoosh whoosh."
Soon after.
As Naruto and his clones launched shurikens and kunai from various angles.
Kakashi, in mid-air, swiftly evaded most of them.
The remaining few.
Kakashi used hand signs.
"Wind Style: Great Breakthrough Jutsu!"
The same C-rank Wind Style ninjutsu that Naruto had used earlier.
But it was clear that, despite being the same technique, Kakashi's Wind Style was significantly more powerful than Naruto's. Not only did he blow away the remaining shurikens and kunai, but he also dispersed over a dozen Naruto clones that were about to strike him. Shurikens flew in all directions, some hit by mistake, others colliding with each other, causing those clones to suffer potentially fatal blows.
Each became a white mist and dissipated.
After landing, Kakashi made a sudden advance.
Directly charging into the swarm of Naruto clones.
As if activating an unbeatable grass-cutting mode.
"Clang!"
"Puchi!"
"Boom!"
Almost none of the clones were a match for Kakashi in a one-on-one confrontation.
"Chua!"
"Puchi!"
The clones were easily swept aside.
In just a dozen or so seconds.
Before Naruto could pose a lethal threat to Kakashi.
Almost half of the hundreds of clones had been eliminated by Kakashi.
This made the real Naruto, hidden among the clones, turn somewhat green. He knew Kakashi was formidable, but he hadn't expected to have no room to retaliate at all. It had only been a few seconds, and Kakashi had already wiped out fifty or sixty of his clones. And this was without Kakashi resorting to large-scale, destructive jutsu; otherwise, all his clones would have been wiped out instantly.
Knowing he was about to be overwhelmed, Naruto found it terrifying how quickly it was happening.
But at least he had succeeded in the first step!
Now, he just needed to continue provoking Kakashi!
Naruto gritted his teeth, and his pupils flashed with a sharp, icy light.
As the dwindling number of clones continued to fight.
"Multiple Shadow Clone Jutsu."
Before the number of clones could dwindle completely.
Naruto formed seals again, creating another hundred or so shadow clones.
Seemingly intending to use this method to wear down Kakashi with sheer numbers.
"Coming again? In that case..."
Seeing the number of clones increase once more.
Kakashi, not wanting to prolong the battle, suddenly swung his body.
Shaking off the clones that had stuck to him.
Then, rapidly forming hand seals.
"Earth Style: Earthquake Jutsu!"
A low shout.
Followed by his palms pressing against the ground.
"Boom, rumble, rumble!"
A dull, resonating sound.
Suddenly.
The ground beneath them, as if being torn apart.
"Ah?"
"What's happening?"
The violently shaking ground.
Some places bulging, others collapsing.
Clones who couldn't control their movements were falling into the gaps.
"Pu pu pu pu."
Even faster than before, they turned into white mist and dissipated.
"Found you!"
And in just such an instant.
Amidst the separation of the crowd.
Kakashi's eyes narrowed as he swiftly identified a figure.
A rapidly advancing figure.
"Whoosh."
Before Naruto could react.
Kakashi's right hand directly seized his neck, targeting the vital point.
The momentarily stiffened Naruto.
"Heh heh, checkmate, Naruto!"
Looking at Naruto, who appeared somewhat stiff in front of him.
Kakashi smiled gently.
"Alright, it's Sasuke's turn now!"
(End of this chapter)